With all your heart/your whole heart
Definition 1 of 1
Pro Tip 1/3Emotional Depth
The phrase adds a heartfelt, profound layer to statements, indicating deep emotions rather than casual feelings. 
He missed his family with all his heart when abroad.
Pro Tip 2/3Personal Commitment
Using this phrase expresses one's dedication or strong intention towards an action or belief. 
She pursued her dreams with her whole heart, undeterred by setbacks.
Pro Tip 3/3Intensity
Indicates an intense level of desire or interest, often more than just wanting or liking something. 
Alex studied with all his heart for his final exams.